Ring oscillators are normally used to determine the speed at which a semiconductor chip is operating. The frequency at which the ring oscillator oscillates is a function of the chip speed. In the realm of ring oscillators, there are many applications such as adaptive voltage scaling (AVS) monitors/clock generators, and voltage binning monitors, where the ring oscillators need to be monitored.
Depending on the circumstance, in some instances, it is required that the ring oscillators oscillate at the frequency that the fastest ring oscillator is oscillating at. On the other hand, in other instances, it is required that the ring oscillators oscillate at the frequency that the slowest ring oscillator is oscillating at. In the past, in order to determine which ring oscillator is the fastest, or which ring oscillator is the slowest, ring oscillators are monitored by reading the results of each oscillator and arithmetically calculating the minimum and maximum frequencies.